| Step | Hyp | Ref | Expression | 
						
							| 1 |  | dynkin.p | ⊢ 𝑃  =  { 𝑠  ∈  𝒫  𝒫  𝑂  ∣  ( fi ‘ 𝑠 )  ⊆  𝑠 } | 
						
							| 2 |  | dynkin.l | ⊢ 𝐿  =  { 𝑠  ∈  𝒫  𝒫  𝑂  ∣  ( ∅  ∈  𝑠  ∧  ∀ 𝑥  ∈  𝑠 ( 𝑂  ∖  𝑥 )  ∈  𝑠  ∧  ∀ 𝑥  ∈  𝒫  𝑠 ( ( 𝑥  ≼  ω  ∧  Disj  𝑦  ∈  𝑥 𝑦 )  →  ∪  𝑥  ∈  𝑠 ) ) } | 
						
							| 3 | 1 | sigapisys | ⊢ ( sigAlgebra ‘ 𝑂 )  ⊆  𝑃 | 
						
							| 4 | 2 | sigaldsys | ⊢ ( sigAlgebra ‘ 𝑂 )  ⊆  𝐿 | 
						
							| 5 | 3 4 | ssini | ⊢ ( sigAlgebra ‘ 𝑂 )  ⊆  ( 𝑃  ∩  𝐿 ) | 
						
							| 6 |  | id | ⊢ ( 𝑡  ∈  ( 𝑃  ∩  𝐿 )  →  𝑡  ∈  ( 𝑃  ∩  𝐿 ) ) | 
						
							| 7 | 6 | elin1d | ⊢ ( 𝑡  ∈  ( 𝑃  ∩  𝐿 )  →  𝑡  ∈  𝑃 ) | 
						
							| 8 | 1 | ispisys | ⊢ ( 𝑡  ∈  𝑃  ↔  ( 𝑡  ∈  𝒫  𝒫  𝑂  ∧  ( fi ‘ 𝑡 )  ⊆  𝑡 ) ) | 
						
							| 9 | 7 8 | sylib | ⊢ ( 𝑡  ∈  ( 𝑃  ∩  𝐿 )  →  ( 𝑡  ∈  𝒫  𝒫  𝑂  ∧  ( fi ‘ 𝑡 )  ⊆  𝑡 ) ) | 
						
							| 10 | 9 | simpld | ⊢ ( 𝑡  ∈  ( 𝑃  ∩  𝐿 )  →  𝑡  ∈  𝒫  𝒫  𝑂 ) | 
						
							| 11 | 10 | elpwid | ⊢ ( 𝑡  ∈  ( 𝑃  ∩  𝐿 )  →  𝑡  ⊆  𝒫  𝑂 ) | 
						
							| 12 |  | dif0 | ⊢ ( 𝑂  ∖  ∅ )  =  𝑂 | 
						
							| 13 | 6 | elin2d | ⊢ ( 𝑡  ∈  ( 𝑃  ∩  𝐿 )  →  𝑡  ∈  𝐿 ) | 
						
							| 14 | 2 | isldsys | ⊢ ( 𝑡  ∈  𝐿  ↔  ( 𝑡  ∈  𝒫  𝒫  𝑂  ∧  ( ∅  ∈  𝑡  ∧  ∀ 𝑥  ∈  𝑡 ( 𝑂  ∖  𝑥 )  ∈  𝑡  ∧  ∀ 𝑥  ∈  𝒫  𝑡 ( ( 𝑥  ≼  ω  ∧  Disj  𝑦  ∈  𝑥 𝑦 )  →  ∪  𝑥  ∈  𝑡 ) ) ) ) | 
						
							| 15 | 13 14 | sylib | ⊢ ( 𝑡  ∈  ( 𝑃  ∩  𝐿 )  →  ( 𝑡  ∈  𝒫  𝒫  𝑂  ∧  ( ∅  ∈  𝑡  ∧  ∀ 𝑥  ∈  𝑡 ( 𝑂  ∖  𝑥 )  ∈  𝑡  ∧  ∀ 𝑥  ∈  𝒫  𝑡 ( ( 𝑥  ≼  ω  ∧  Disj  𝑦  ∈  𝑥 𝑦 )  →  ∪  𝑥  ∈  𝑡 ) ) ) ) | 
						
							| 16 | 15 | simprd | ⊢ ( 𝑡  ∈  ( 𝑃  ∩  𝐿 )  →  ( ∅  ∈  𝑡  ∧  ∀ 𝑥  ∈  𝑡 ( 𝑂  ∖  𝑥 )  ∈  𝑡  ∧  ∀ 𝑥  ∈  𝒫  𝑡 ( ( 𝑥  ≼  ω  ∧  Disj  𝑦  ∈  𝑥 𝑦 )  →  ∪  𝑥  ∈  𝑡 ) ) ) | 
						
							| 17 | 16 | simp2d | ⊢ ( 𝑡  ∈  ( 𝑃  ∩  𝐿 )  →  ∀ 𝑥  ∈  𝑡 ( 𝑂  ∖  𝑥 )  ∈  𝑡 ) | 
						
							| 18 | 16 | simp1d | ⊢ ( 𝑡  ∈  ( 𝑃  ∩  𝐿 )  →  ∅  ∈  𝑡 ) | 
						
							| 19 |  | difeq2 | ⊢ ( 𝑥  =  ∅  →  ( 𝑂  ∖  𝑥 )  =  ( 𝑂  ∖  ∅ ) ) | 
						
							| 20 |  | eqidd | ⊢ ( 𝑥  =  ∅  →  𝑡  =  𝑡 ) | 
						
							| 21 | 19 20 | eleq12d | ⊢ ( 𝑥  =  ∅  →  ( ( 𝑂  ∖  𝑥 )  ∈  𝑡  ↔  ( 𝑂  ∖  ∅ )  ∈  𝑡 ) ) | 
						
							| 22 | 21 | rspcv | ⊢ ( ∅  ∈  𝑡  →  ( ∀ 𝑥  ∈  𝑡 ( 𝑂  ∖  𝑥 )  ∈  𝑡  →  ( 𝑂  ∖  ∅ )  ∈  𝑡 ) ) | 
						
							| 23 | 18 22 | syl | ⊢ ( 𝑡  ∈  ( 𝑃  ∩  𝐿 )  →  ( ∀ 𝑥  ∈  𝑡 ( 𝑂  ∖  𝑥 )  ∈  𝑡  →  ( 𝑂  ∖  ∅ )  ∈  𝑡 ) ) | 
						
							| 24 | 17 23 | mpd | ⊢ ( 𝑡  ∈  ( 𝑃  ∩  𝐿 )  →  ( 𝑂  ∖  ∅ )  ∈  𝑡 ) | 
						
							| 25 | 12 24 | eqeltrrid | ⊢ ( 𝑡  ∈  ( 𝑃  ∩  𝐿 )  →  𝑂  ∈  𝑡 ) | 
						
							| 26 |  | unieq | ⊢ ( 𝑥  =  ∅  →  ∪  𝑥  =  ∪  ∅ ) | 
						
							| 27 |  | uni0 | ⊢ ∪  ∅  =  ∅ | 
						
							| 28 | 26 27 | eqtrdi | ⊢ ( 𝑥  =  ∅  →  ∪  𝑥  =  ∅ ) | 
						
							| 29 | 28 | adantl | ⊢ ( ( ( ( 𝑡  ∈  ( 𝑃  ∩  𝐿 )  ∧  𝑥  ∈  𝒫  𝑡 )  ∧  𝑥  ≼  ω )  ∧  𝑥  =  ∅ )  →  ∪  𝑥  =  ∅ ) | 
						
							| 30 | 18 | ad3antrrr | ⊢ ( ( ( ( 𝑡  ∈  ( 𝑃  ∩  𝐿 )  ∧  𝑥  ∈  𝒫  𝑡 )  ∧  𝑥  ≼  ω )  ∧  𝑥  =  ∅ )  →  ∅  ∈  𝑡 ) | 
						
							| 31 | 29 30 | eqeltrd | ⊢ ( ( ( ( 𝑡  ∈  ( 𝑃  ∩  𝐿 )  ∧  𝑥  ∈  𝒫  𝑡 )  ∧  𝑥  ≼  ω )  ∧  𝑥  =  ∅ )  →  ∪  𝑥  ∈  𝑡 ) | 
						
							| 32 |  | vex | ⊢ 𝑥  ∈  V | 
						
							| 33 | 32 | 0sdom | ⊢ ( ∅  ≺  𝑥  ↔  𝑥  ≠  ∅ ) | 
						
							| 34 | 33 | biimpri | ⊢ ( 𝑥  ≠  ∅  →  ∅  ≺  𝑥 ) | 
						
							| 35 | 34 | adantl | ⊢ ( ( ( ( 𝑡  ∈  ( 𝑃  ∩  𝐿 )  ∧  𝑥  ∈  𝒫  𝑡 )  ∧  𝑥  ≼  ω )  ∧  𝑥  ≠  ∅ )  →  ∅  ≺  𝑥 ) | 
						
							| 36 |  | simplr | ⊢ ( ( ( ( 𝑡  ∈  ( 𝑃  ∩  𝐿 )  ∧  𝑥  ∈  𝒫  𝑡 )  ∧  𝑥  ≼  ω )  ∧  𝑥  ≠  ∅ )  →  𝑥  ≼  ω ) | 
						
							| 37 |  | nnenom | ⊢ ℕ  ≈  ω | 
						
							| 38 | 37 | ensymi | ⊢ ω  ≈  ℕ | 
						
							| 39 |  | domentr | ⊢ ( ( 𝑥  ≼  ω  ∧  ω  ≈  ℕ )  →  𝑥  ≼  ℕ ) | 
						
							| 40 | 36 38 39 | sylancl | ⊢ ( ( ( ( 𝑡  ∈  ( 𝑃  ∩  𝐿 )  ∧  𝑥  ∈  𝒫  𝑡 )  ∧  𝑥  ≼  ω )  ∧  𝑥  ≠  ∅ )  →  𝑥  ≼  ℕ ) | 
						
							| 41 |  | fodomr | ⊢ ( ( ∅  ≺  𝑥  ∧  𝑥  ≼  ℕ )  →  ∃ 𝑓 𝑓 : ℕ –onto→ 𝑥 ) | 
						
							| 42 | 35 40 41 | syl2anc | ⊢ ( ( ( ( 𝑡  ∈  ( 𝑃  ∩  𝐿 )  ∧  𝑥  ∈  𝒫  𝑡 )  ∧  𝑥  ≼  ω )  ∧  𝑥  ≠  ∅ )  →  ∃ 𝑓 𝑓 : ℕ –onto→ 𝑥 ) | 
						
							| 43 |  | fveq2 | ⊢ ( 𝑛  =  𝑖  →  ( 𝑓 ‘ 𝑛 )  =  ( 𝑓 ‘ 𝑖 ) ) | 
						
							| 44 | 43 | iundisj | ⊢ ∪  𝑛  ∈  ℕ ( 𝑓 ‘ 𝑛 )  =  ∪  𝑛  ∈  ℕ ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) | 
						
							| 45 |  | fofn | ⊢ ( 𝑓 : ℕ –onto→ 𝑥  →  𝑓  Fn  ℕ ) | 
						
							| 46 |  | fniunfv | ⊢ ( 𝑓  Fn  ℕ  →  ∪  𝑛  ∈  ℕ ( 𝑓 ‘ 𝑛 )  =  ∪  ran  𝑓 ) | 
						
							| 47 | 45 46 | syl | ⊢ ( 𝑓 : ℕ –onto→ 𝑥  →  ∪  𝑛  ∈  ℕ ( 𝑓 ‘ 𝑛 )  =  ∪  ran  𝑓 ) | 
						
							| 48 |  | forn | ⊢ ( 𝑓 : ℕ –onto→ 𝑥  →  ran  𝑓  =  𝑥 ) | 
						
							| 49 | 48 | unieqd | ⊢ ( 𝑓 : ℕ –onto→ 𝑥  →  ∪  ran  𝑓  =  ∪  𝑥 ) | 
						
							| 50 | 47 49 | eqtrd | ⊢ ( 𝑓 : ℕ –onto→ 𝑥  →  ∪  𝑛  ∈  ℕ ( 𝑓 ‘ 𝑛 )  =  ∪  𝑥 ) | 
						
							| 51 | 44 50 | eqtr3id | ⊢ ( 𝑓 : ℕ –onto→ 𝑥  →  ∪  𝑛  ∈  ℕ ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) )  =  ∪  𝑥 ) | 
						
							| 52 | 51 | adantl | ⊢ ( ( ( ( ( 𝑡  ∈  ( 𝑃  ∩  𝐿 )  ∧  𝑥  ∈  𝒫  𝑡 )  ∧  𝑥  ≼  ω )  ∧  𝑥  ≠  ∅ )  ∧  𝑓 : ℕ –onto→ 𝑥 )  →  ∪  𝑛  ∈  ℕ ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) )  =  ∪  𝑥 ) | 
						
							| 53 |  | fvex | ⊢ ( 𝑓 ‘ 𝑛 )  ∈  V | 
						
							| 54 |  | difexg | ⊢ ( ( 𝑓 ‘ 𝑛 )  ∈  V  →  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) )  ∈  V ) | 
						
							| 55 | 53 54 | ax-mp | ⊢ ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) )  ∈  V | 
						
							| 56 | 55 | dfiun3 | ⊢ ∪  𝑛  ∈  ℕ ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) )  =  ∪  ran  ( 𝑛  ∈  ℕ  ↦  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) ) | 
						
							| 57 |  | nfv | ⊢ Ⅎ 𝑛 ( ( ( ( 𝑡  ∈  ( 𝑃  ∩  𝐿 )  ∧  𝑥  ∈  𝒫  𝑡 )  ∧  𝑥  ≼  ω )  ∧  𝑥  ≠  ∅ )  ∧  𝑓 : ℕ –onto→ 𝑥 ) | 
						
							| 58 |  | nfcv | ⊢ Ⅎ 𝑛 𝑦 | 
						
							| 59 |  | nfmpt1 | ⊢ Ⅎ 𝑛 ( 𝑛  ∈  ℕ  ↦  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) ) | 
						
							| 60 | 59 | nfrn | ⊢ Ⅎ 𝑛 ran  ( 𝑛  ∈  ℕ  ↦  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) ) | 
						
							| 61 | 58 60 | nfel | ⊢ Ⅎ 𝑛 𝑦  ∈  ran  ( 𝑛  ∈  ℕ  ↦  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) ) | 
						
							| 62 | 57 61 | nfan | ⊢ Ⅎ 𝑛 ( ( ( ( ( 𝑡  ∈  ( 𝑃  ∩  𝐿 )  ∧  𝑥  ∈  𝒫  𝑡 )  ∧  𝑥  ≼  ω )  ∧  𝑥  ≠  ∅ )  ∧  𝑓 : ℕ –onto→ 𝑥 )  ∧  𝑦  ∈  ran  ( 𝑛  ∈  ℕ  ↦  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) ) ) | 
						
							| 63 |  | simpr | ⊢ ( ( ( ( ( ( ( ( 𝑡  ∈  ( 𝑃  ∩  𝐿 )  ∧  𝑥  ∈  𝒫  𝑡 )  ∧  𝑥  ≼  ω )  ∧  𝑥  ≠  ∅ )  ∧  𝑓 : ℕ –onto→ 𝑥 )  ∧  𝑦  ∈  ran  ( 𝑛  ∈  ℕ  ↦  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) ) )  ∧  𝑛  ∈  ℕ )  ∧  𝑦  =  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) )  →  𝑦  =  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) ) | 
						
							| 64 |  | nfv | ⊢ Ⅎ 𝑖 ( ( ( ( 𝑡  ∈  ( 𝑃  ∩  𝐿 )  ∧  𝑥  ∈  𝒫  𝑡 )  ∧  𝑥  ≼  ω )  ∧  𝑥  ≠  ∅ )  ∧  𝑓 : ℕ –onto→ 𝑥 ) | 
						
							| 65 |  | nfcv | ⊢ Ⅎ 𝑖 𝑦 | 
						
							| 66 |  | nfcv | ⊢ Ⅎ 𝑖 ℕ | 
						
							| 67 |  | nfcv | ⊢ Ⅎ 𝑖 ( 𝑓 ‘ 𝑛 ) | 
						
							| 68 |  | nfiu1 | ⊢ Ⅎ 𝑖 ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) | 
						
							| 69 | 67 68 | nfdif | ⊢ Ⅎ 𝑖 ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) | 
						
							| 70 | 66 69 | nfmpt | ⊢ Ⅎ 𝑖 ( 𝑛  ∈  ℕ  ↦  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) ) | 
						
							| 71 | 70 | nfrn | ⊢ Ⅎ 𝑖 ran  ( 𝑛  ∈  ℕ  ↦  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) ) | 
						
							| 72 | 65 71 | nfel | ⊢ Ⅎ 𝑖 𝑦  ∈  ran  ( 𝑛  ∈  ℕ  ↦  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) ) | 
						
							| 73 | 64 72 | nfan | ⊢ Ⅎ 𝑖 ( ( ( ( ( 𝑡  ∈  ( 𝑃  ∩  𝐿 )  ∧  𝑥  ∈  𝒫  𝑡 )  ∧  𝑥  ≼  ω )  ∧  𝑥  ≠  ∅ )  ∧  𝑓 : ℕ –onto→ 𝑥 )  ∧  𝑦  ∈  ran  ( 𝑛  ∈  ℕ  ↦  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) ) ) | 
						
							| 74 |  | nfv | ⊢ Ⅎ 𝑖 𝑛  ∈  ℕ | 
						
							| 75 | 73 74 | nfan | ⊢ Ⅎ 𝑖 ( ( ( ( ( ( 𝑡  ∈  ( 𝑃  ∩  𝐿 )  ∧  𝑥  ∈  𝒫  𝑡 )  ∧  𝑥  ≼  ω )  ∧  𝑥  ≠  ∅ )  ∧  𝑓 : ℕ –onto→ 𝑥 )  ∧  𝑦  ∈  ran  ( 𝑛  ∈  ℕ  ↦  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) ) )  ∧  𝑛  ∈  ℕ ) | 
						
							| 76 | 65 69 | nfeq | ⊢ Ⅎ 𝑖 𝑦  =  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) | 
						
							| 77 | 75 76 | nfan | ⊢ Ⅎ 𝑖 ( ( ( ( ( ( ( 𝑡  ∈  ( 𝑃  ∩  𝐿 )  ∧  𝑥  ∈  𝒫  𝑡 )  ∧  𝑥  ≼  ω )  ∧  𝑥  ≠  ∅ )  ∧  𝑓 : ℕ –onto→ 𝑥 )  ∧  𝑦  ∈  ran  ( 𝑛  ∈  ℕ  ↦  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) ) )  ∧  𝑛  ∈  ℕ )  ∧  𝑦  =  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) ) | 
						
							| 78 | 6 | ad7antr | ⊢ ( ( ( ( ( ( ( ( 𝑡  ∈  ( 𝑃  ∩  𝐿 )  ∧  𝑥  ∈  𝒫  𝑡 )  ∧  𝑥  ≼  ω )  ∧  𝑥  ≠  ∅ )  ∧  𝑓 : ℕ –onto→ 𝑥 )  ∧  𝑦  ∈  ran  ( 𝑛  ∈  ℕ  ↦  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) ) )  ∧  𝑛  ∈  ℕ )  ∧  𝑦  =  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) )  →  𝑡  ∈  ( 𝑃  ∩  𝐿 ) ) | 
						
							| 79 |  | simp-4r | ⊢ ( ( ( ( ( 𝑡  ∈  ( 𝑃  ∩  𝐿 )  ∧  𝑥  ∈  𝒫  𝑡 )  ∧  𝑥  ≼  ω )  ∧  𝑥  ≠  ∅ )  ∧  𝑓 : ℕ –onto→ 𝑥 )  →  𝑥  ∈  𝒫  𝑡 ) | 
						
							| 80 | 79 | ad3antrrr | ⊢ ( ( ( ( ( ( ( ( 𝑡  ∈  ( 𝑃  ∩  𝐿 )  ∧  𝑥  ∈  𝒫  𝑡 )  ∧  𝑥  ≼  ω )  ∧  𝑥  ≠  ∅ )  ∧  𝑓 : ℕ –onto→ 𝑥 )  ∧  𝑦  ∈  ran  ( 𝑛  ∈  ℕ  ↦  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) ) )  ∧  𝑛  ∈  ℕ )  ∧  𝑦  =  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) )  →  𝑥  ∈  𝒫  𝑡 ) | 
						
							| 81 | 80 | elpwid | ⊢ ( ( ( ( ( ( ( ( 𝑡  ∈  ( 𝑃  ∩  𝐿 )  ∧  𝑥  ∈  𝒫  𝑡 )  ∧  𝑥  ≼  ω )  ∧  𝑥  ≠  ∅ )  ∧  𝑓 : ℕ –onto→ 𝑥 )  ∧  𝑦  ∈  ran  ( 𝑛  ∈  ℕ  ↦  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) ) )  ∧  𝑛  ∈  ℕ )  ∧  𝑦  =  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) )  →  𝑥  ⊆  𝑡 ) | 
						
							| 82 |  | fof | ⊢ ( 𝑓 : ℕ –onto→ 𝑥  →  𝑓 : ℕ ⟶ 𝑥 ) | 
						
							| 83 | 82 | ad4antlr | ⊢ ( ( ( ( ( ( ( ( 𝑡  ∈  ( 𝑃  ∩  𝐿 )  ∧  𝑥  ∈  𝒫  𝑡 )  ∧  𝑥  ≼  ω )  ∧  𝑥  ≠  ∅ )  ∧  𝑓 : ℕ –onto→ 𝑥 )  ∧  𝑦  ∈  ran  ( 𝑛  ∈  ℕ  ↦  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) ) )  ∧  𝑛  ∈  ℕ )  ∧  𝑦  =  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) )  →  𝑓 : ℕ ⟶ 𝑥 ) | 
						
							| 84 |  | simplr | ⊢ ( ( ( ( ( ( ( ( 𝑡  ∈  ( 𝑃  ∩  𝐿 )  ∧  𝑥  ∈  𝒫  𝑡 )  ∧  𝑥  ≼  ω )  ∧  𝑥  ≠  ∅ )  ∧  𝑓 : ℕ –onto→ 𝑥 )  ∧  𝑦  ∈  ran  ( 𝑛  ∈  ℕ  ↦  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) ) )  ∧  𝑛  ∈  ℕ )  ∧  𝑦  =  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) )  →  𝑛  ∈  ℕ ) | 
						
							| 85 | 83 84 | ffvelcdmd | ⊢ ( ( ( ( ( ( ( ( 𝑡  ∈  ( 𝑃  ∩  𝐿 )  ∧  𝑥  ∈  𝒫  𝑡 )  ∧  𝑥  ≼  ω )  ∧  𝑥  ≠  ∅ )  ∧  𝑓 : ℕ –onto→ 𝑥 )  ∧  𝑦  ∈  ran  ( 𝑛  ∈  ℕ  ↦  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) ) )  ∧  𝑛  ∈  ℕ )  ∧  𝑦  =  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) )  →  ( 𝑓 ‘ 𝑛 )  ∈  𝑥 ) | 
						
							| 86 | 81 85 | sseldd | ⊢ ( ( ( ( ( ( ( ( 𝑡  ∈  ( 𝑃  ∩  𝐿 )  ∧  𝑥  ∈  𝒫  𝑡 )  ∧  𝑥  ≼  ω )  ∧  𝑥  ≠  ∅ )  ∧  𝑓 : ℕ –onto→ 𝑥 )  ∧  𝑦  ∈  ran  ( 𝑛  ∈  ℕ  ↦  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) ) )  ∧  𝑛  ∈  ℕ )  ∧  𝑦  =  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) )  →  ( 𝑓 ‘ 𝑛 )  ∈  𝑡 ) | 
						
							| 87 |  | fzofi | ⊢ ( 1 ..^ 𝑛 )  ∈  Fin | 
						
							| 88 | 87 | a1i | ⊢ ( ( ( ( ( ( ( ( 𝑡  ∈  ( 𝑃  ∩  𝐿 )  ∧  𝑥  ∈  𝒫  𝑡 )  ∧  𝑥  ≼  ω )  ∧  𝑥  ≠  ∅ )  ∧  𝑓 : ℕ –onto→ 𝑥 )  ∧  𝑦  ∈  ran  ( 𝑛  ∈  ℕ  ↦  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) ) )  ∧  𝑛  ∈  ℕ )  ∧  𝑦  =  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) )  →  ( 1 ..^ 𝑛 )  ∈  Fin ) | 
						
							| 89 | 81 | adantr | ⊢ ( ( ( ( ( ( ( ( ( 𝑡  ∈  ( 𝑃  ∩  𝐿 )  ∧  𝑥  ∈  𝒫  𝑡 )  ∧  𝑥  ≼  ω )  ∧  𝑥  ≠  ∅ )  ∧  𝑓 : ℕ –onto→ 𝑥 )  ∧  𝑦  ∈  ran  ( 𝑛  ∈  ℕ  ↦  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) ) )  ∧  𝑛  ∈  ℕ )  ∧  𝑦  =  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) )  ∧  𝑖  ∈  ( 1 ..^ 𝑛 ) )  →  𝑥  ⊆  𝑡 ) | 
						
							| 90 | 83 | adantr | ⊢ ( ( ( ( ( ( ( ( ( 𝑡  ∈  ( 𝑃  ∩  𝐿 )  ∧  𝑥  ∈  𝒫  𝑡 )  ∧  𝑥  ≼  ω )  ∧  𝑥  ≠  ∅ )  ∧  𝑓 : ℕ –onto→ 𝑥 )  ∧  𝑦  ∈  ran  ( 𝑛  ∈  ℕ  ↦  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) ) )  ∧  𝑛  ∈  ℕ )  ∧  𝑦  =  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) )  ∧  𝑖  ∈  ( 1 ..^ 𝑛 ) )  →  𝑓 : ℕ ⟶ 𝑥 ) | 
						
							| 91 |  | fzossnn | ⊢ ( 1 ..^ 𝑛 )  ⊆  ℕ | 
						
							| 92 | 91 | a1i | ⊢ ( ( ( ( ( ( ( ( 𝑡  ∈  ( 𝑃  ∩  𝐿 )  ∧  𝑥  ∈  𝒫  𝑡 )  ∧  𝑥  ≼  ω )  ∧  𝑥  ≠  ∅ )  ∧  𝑓 : ℕ –onto→ 𝑥 )  ∧  𝑦  ∈  ran  ( 𝑛  ∈  ℕ  ↦  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) ) )  ∧  𝑛  ∈  ℕ )  ∧  𝑦  =  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) )  →  ( 1 ..^ 𝑛 )  ⊆  ℕ ) | 
						
							| 93 | 92 | sselda | ⊢ ( ( ( ( ( ( ( ( ( 𝑡  ∈  ( 𝑃  ∩  𝐿 )  ∧  𝑥  ∈  𝒫  𝑡 )  ∧  𝑥  ≼  ω )  ∧  𝑥  ≠  ∅ )  ∧  𝑓 : ℕ –onto→ 𝑥 )  ∧  𝑦  ∈  ran  ( 𝑛  ∈  ℕ  ↦  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) ) )  ∧  𝑛  ∈  ℕ )  ∧  𝑦  =  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) )  ∧  𝑖  ∈  ( 1 ..^ 𝑛 ) )  →  𝑖  ∈  ℕ ) | 
						
							| 94 | 90 93 | ffvelcdmd | ⊢ ( ( ( ( ( ( ( ( ( 𝑡  ∈  ( 𝑃  ∩  𝐿 )  ∧  𝑥  ∈  𝒫  𝑡 )  ∧  𝑥  ≼  ω )  ∧  𝑥  ≠  ∅ )  ∧  𝑓 : ℕ –onto→ 𝑥 )  ∧  𝑦  ∈  ran  ( 𝑛  ∈  ℕ  ↦  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) ) )  ∧  𝑛  ∈  ℕ )  ∧  𝑦  =  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) )  ∧  𝑖  ∈  ( 1 ..^ 𝑛 ) )  →  ( 𝑓 ‘ 𝑖 )  ∈  𝑥 ) | 
						
							| 95 | 89 94 | sseldd | ⊢ ( ( ( ( ( ( ( ( ( 𝑡  ∈  ( 𝑃  ∩  𝐿 )  ∧  𝑥  ∈  𝒫  𝑡 )  ∧  𝑥  ≼  ω )  ∧  𝑥  ≠  ∅ )  ∧  𝑓 : ℕ –onto→ 𝑥 )  ∧  𝑦  ∈  ran  ( 𝑛  ∈  ℕ  ↦  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) ) )  ∧  𝑛  ∈  ℕ )  ∧  𝑦  =  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) )  ∧  𝑖  ∈  ( 1 ..^ 𝑛 ) )  →  ( 𝑓 ‘ 𝑖 )  ∈  𝑡 ) | 
						
							| 96 | 1 2 77 78 86 88 95 | sigapildsyslem | ⊢ ( ( ( ( ( ( ( ( 𝑡  ∈  ( 𝑃  ∩  𝐿 )  ∧  𝑥  ∈  𝒫  𝑡 )  ∧  𝑥  ≼  ω )  ∧  𝑥  ≠  ∅ )  ∧  𝑓 : ℕ –onto→ 𝑥 )  ∧  𝑦  ∈  ran  ( 𝑛  ∈  ℕ  ↦  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) ) )  ∧  𝑛  ∈  ℕ )  ∧  𝑦  =  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) )  →  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) )  ∈  𝑡 ) | 
						
							| 97 | 63 96 | eqeltrd | ⊢ ( ( ( ( ( ( ( ( 𝑡  ∈  ( 𝑃  ∩  𝐿 )  ∧  𝑥  ∈  𝒫  𝑡 )  ∧  𝑥  ≼  ω )  ∧  𝑥  ≠  ∅ )  ∧  𝑓 : ℕ –onto→ 𝑥 )  ∧  𝑦  ∈  ran  ( 𝑛  ∈  ℕ  ↦  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) ) )  ∧  𝑛  ∈  ℕ )  ∧  𝑦  =  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) )  →  𝑦  ∈  𝑡 ) | 
						
							| 98 |  | simpr | ⊢ ( ( ( ( ( ( 𝑡  ∈  ( 𝑃  ∩  𝐿 )  ∧  𝑥  ∈  𝒫  𝑡 )  ∧  𝑥  ≼  ω )  ∧  𝑥  ≠  ∅ )  ∧  𝑓 : ℕ –onto→ 𝑥 )  ∧  𝑦  ∈  ran  ( 𝑛  ∈  ℕ  ↦  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) ) )  →  𝑦  ∈  ran  ( 𝑛  ∈  ℕ  ↦  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) ) ) | 
						
							| 99 |  | eqid | ⊢ ( 𝑛  ∈  ℕ  ↦  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) )  =  ( 𝑛  ∈  ℕ  ↦  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) ) | 
						
							| 100 | 99 55 | elrnmpti | ⊢ ( 𝑦  ∈  ran  ( 𝑛  ∈  ℕ  ↦  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) )  ↔  ∃ 𝑛  ∈  ℕ 𝑦  =  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) ) | 
						
							| 101 | 98 100 | sylib | ⊢ ( ( ( ( ( ( 𝑡  ∈  ( 𝑃  ∩  𝐿 )  ∧  𝑥  ∈  𝒫  𝑡 )  ∧  𝑥  ≼  ω )  ∧  𝑥  ≠  ∅ )  ∧  𝑓 : ℕ –onto→ 𝑥 )  ∧  𝑦  ∈  ran  ( 𝑛  ∈  ℕ  ↦  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) ) )  →  ∃ 𝑛  ∈  ℕ 𝑦  =  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) ) | 
						
							| 102 | 62 97 101 | r19.29af | ⊢ ( ( ( ( ( ( 𝑡  ∈  ( 𝑃  ∩  𝐿 )  ∧  𝑥  ∈  𝒫  𝑡 )  ∧  𝑥  ≼  ω )  ∧  𝑥  ≠  ∅ )  ∧  𝑓 : ℕ –onto→ 𝑥 )  ∧  𝑦  ∈  ran  ( 𝑛  ∈  ℕ  ↦  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) ) )  →  𝑦  ∈  𝑡 ) | 
						
							| 103 | 102 | ex | ⊢ ( ( ( ( ( 𝑡  ∈  ( 𝑃  ∩  𝐿 )  ∧  𝑥  ∈  𝒫  𝑡 )  ∧  𝑥  ≼  ω )  ∧  𝑥  ≠  ∅ )  ∧  𝑓 : ℕ –onto→ 𝑥 )  →  ( 𝑦  ∈  ran  ( 𝑛  ∈  ℕ  ↦  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) )  →  𝑦  ∈  𝑡 ) ) | 
						
							| 104 | 103 | ssrdv | ⊢ ( ( ( ( ( 𝑡  ∈  ( 𝑃  ∩  𝐿 )  ∧  𝑥  ∈  𝒫  𝑡 )  ∧  𝑥  ≼  ω )  ∧  𝑥  ≠  ∅ )  ∧  𝑓 : ℕ –onto→ 𝑥 )  →  ran  ( 𝑛  ∈  ℕ  ↦  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) )  ⊆  𝑡 ) | 
						
							| 105 |  | nnex | ⊢ ℕ  ∈  V | 
						
							| 106 | 105 | mptex | ⊢ ( 𝑛  ∈  ℕ  ↦  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) )  ∈  V | 
						
							| 107 | 106 | rnex | ⊢ ran  ( 𝑛  ∈  ℕ  ↦  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) )  ∈  V | 
						
							| 108 |  | elpwg | ⊢ ( ran  ( 𝑛  ∈  ℕ  ↦  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) )  ∈  V  →  ( ran  ( 𝑛  ∈  ℕ  ↦  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) )  ∈  𝒫  𝑡  ↔  ran  ( 𝑛  ∈  ℕ  ↦  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) )  ⊆  𝑡 ) ) | 
						
							| 109 | 107 108 | ax-mp | ⊢ ( ran  ( 𝑛  ∈  ℕ  ↦  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) )  ∈  𝒫  𝑡  ↔  ran  ( 𝑛  ∈  ℕ  ↦  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) )  ⊆  𝑡 ) | 
						
							| 110 | 104 109 | sylibr | ⊢ ( ( ( ( ( 𝑡  ∈  ( 𝑃  ∩  𝐿 )  ∧  𝑥  ∈  𝒫  𝑡 )  ∧  𝑥  ≼  ω )  ∧  𝑥  ≠  ∅ )  ∧  𝑓 : ℕ –onto→ 𝑥 )  →  ran  ( 𝑛  ∈  ℕ  ↦  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) )  ∈  𝒫  𝑡 ) | 
						
							| 111 | 16 | simp3d | ⊢ ( 𝑡  ∈  ( 𝑃  ∩  𝐿 )  →  ∀ 𝑥  ∈  𝒫  𝑡 ( ( 𝑥  ≼  ω  ∧  Disj  𝑦  ∈  𝑥 𝑦 )  →  ∪  𝑥  ∈  𝑡 ) ) | 
						
							| 112 | 111 | ad4antr | ⊢ ( ( ( ( ( 𝑡  ∈  ( 𝑃  ∩  𝐿 )  ∧  𝑥  ∈  𝒫  𝑡 )  ∧  𝑥  ≼  ω )  ∧  𝑥  ≠  ∅ )  ∧  𝑓 : ℕ –onto→ 𝑥 )  →  ∀ 𝑥  ∈  𝒫  𝑡 ( ( 𝑥  ≼  ω  ∧  Disj  𝑦  ∈  𝑥 𝑦 )  →  ∪  𝑥  ∈  𝑡 ) ) | 
						
							| 113 |  | nnct | ⊢ ℕ  ≼  ω | 
						
							| 114 |  | mptct | ⊢ ( ℕ  ≼  ω  →  ( 𝑛  ∈  ℕ  ↦  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) )  ≼  ω ) | 
						
							| 115 | 113 114 | ax-mp | ⊢ ( 𝑛  ∈  ℕ  ↦  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) )  ≼  ω | 
						
							| 116 |  | rnct | ⊢ ( ( 𝑛  ∈  ℕ  ↦  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) )  ≼  ω  →  ran  ( 𝑛  ∈  ℕ  ↦  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) )  ≼  ω ) | 
						
							| 117 | 115 116 | mp1i | ⊢ ( ( ( ( ( 𝑡  ∈  ( 𝑃  ∩  𝐿 )  ∧  𝑥  ∈  𝒫  𝑡 )  ∧  𝑥  ≼  ω )  ∧  𝑥  ≠  ∅ )  ∧  𝑓 : ℕ –onto→ 𝑥 )  →  ran  ( 𝑛  ∈  ℕ  ↦  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) )  ≼  ω ) | 
						
							| 118 | 43 | iundisj2 | ⊢ Disj  𝑛  ∈  ℕ ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) | 
						
							| 119 |  | disjrnmpt | ⊢ ( Disj  𝑛  ∈  ℕ ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) )  →  Disj  𝑦  ∈  ran  ( 𝑛  ∈  ℕ  ↦  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) ) 𝑦 ) | 
						
							| 120 | 118 119 | mp1i | ⊢ ( ( ( ( ( 𝑡  ∈  ( 𝑃  ∩  𝐿 )  ∧  𝑥  ∈  𝒫  𝑡 )  ∧  𝑥  ≼  ω )  ∧  𝑥  ≠  ∅ )  ∧  𝑓 : ℕ –onto→ 𝑥 )  →  Disj  𝑦  ∈  ran  ( 𝑛  ∈  ℕ  ↦  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) ) 𝑦 ) | 
						
							| 121 |  | breq1 | ⊢ ( 𝑥  =  ran  ( 𝑛  ∈  ℕ  ↦  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) )  →  ( 𝑥  ≼  ω  ↔  ran  ( 𝑛  ∈  ℕ  ↦  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) )  ≼  ω ) ) | 
						
							| 122 |  | disjeq1 | ⊢ ( 𝑥  =  ran  ( 𝑛  ∈  ℕ  ↦  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) )  →  ( Disj  𝑦  ∈  𝑥 𝑦  ↔  Disj  𝑦  ∈  ran  ( 𝑛  ∈  ℕ  ↦  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) ) 𝑦 ) ) | 
						
							| 123 | 121 122 | anbi12d | ⊢ ( 𝑥  =  ran  ( 𝑛  ∈  ℕ  ↦  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) )  →  ( ( 𝑥  ≼  ω  ∧  Disj  𝑦  ∈  𝑥 𝑦 )  ↔  ( ran  ( 𝑛  ∈  ℕ  ↦  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) )  ≼  ω  ∧  Disj  𝑦  ∈  ran  ( 𝑛  ∈  ℕ  ↦  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) ) 𝑦 ) ) ) | 
						
							| 124 |  | unieq | ⊢ ( 𝑥  =  ran  ( 𝑛  ∈  ℕ  ↦  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) )  →  ∪  𝑥  =  ∪  ran  ( 𝑛  ∈  ℕ  ↦  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) ) ) | 
						
							| 125 | 124 | eleq1d | ⊢ ( 𝑥  =  ran  ( 𝑛  ∈  ℕ  ↦  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) )  →  ( ∪  𝑥  ∈  𝑡  ↔  ∪  ran  ( 𝑛  ∈  ℕ  ↦  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) )  ∈  𝑡 ) ) | 
						
							| 126 | 123 125 | imbi12d | ⊢ ( 𝑥  =  ran  ( 𝑛  ∈  ℕ  ↦  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) )  →  ( ( ( 𝑥  ≼  ω  ∧  Disj  𝑦  ∈  𝑥 𝑦 )  →  ∪  𝑥  ∈  𝑡 )  ↔  ( ( ran  ( 𝑛  ∈  ℕ  ↦  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) )  ≼  ω  ∧  Disj  𝑦  ∈  ran  ( 𝑛  ∈  ℕ  ↦  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) ) 𝑦 )  →  ∪  ran  ( 𝑛  ∈  ℕ  ↦  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) )  ∈  𝑡 ) ) ) | 
						
							| 127 | 126 | rspcv | ⊢ ( ran  ( 𝑛  ∈  ℕ  ↦  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) )  ∈  𝒫  𝑡  →  ( ∀ 𝑥  ∈  𝒫  𝑡 ( ( 𝑥  ≼  ω  ∧  Disj  𝑦  ∈  𝑥 𝑦 )  →  ∪  𝑥  ∈  𝑡 )  →  ( ( ran  ( 𝑛  ∈  ℕ  ↦  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) )  ≼  ω  ∧  Disj  𝑦  ∈  ran  ( 𝑛  ∈  ℕ  ↦  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) ) 𝑦 )  →  ∪  ran  ( 𝑛  ∈  ℕ  ↦  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) )  ∈  𝑡 ) ) ) | 
						
							| 128 | 127 | imp | ⊢ ( ( ran  ( 𝑛  ∈  ℕ  ↦  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) )  ∈  𝒫  𝑡  ∧  ∀ 𝑥  ∈  𝒫  𝑡 ( ( 𝑥  ≼  ω  ∧  Disj  𝑦  ∈  𝑥 𝑦 )  →  ∪  𝑥  ∈  𝑡 ) )  →  ( ( ran  ( 𝑛  ∈  ℕ  ↦  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) )  ≼  ω  ∧  Disj  𝑦  ∈  ran  ( 𝑛  ∈  ℕ  ↦  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) ) 𝑦 )  →  ∪  ran  ( 𝑛  ∈  ℕ  ↦  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) )  ∈  𝑡 ) ) | 
						
							| 129 | 128 | imp | ⊢ ( ( ( ran  ( 𝑛  ∈  ℕ  ↦  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) )  ∈  𝒫  𝑡  ∧  ∀ 𝑥  ∈  𝒫  𝑡 ( ( 𝑥  ≼  ω  ∧  Disj  𝑦  ∈  𝑥 𝑦 )  →  ∪  𝑥  ∈  𝑡 ) )  ∧  ( ran  ( 𝑛  ∈  ℕ  ↦  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) )  ≼  ω  ∧  Disj  𝑦  ∈  ran  ( 𝑛  ∈  ℕ  ↦  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) ) 𝑦 ) )  →  ∪  ran  ( 𝑛  ∈  ℕ  ↦  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) )  ∈  𝑡 ) | 
						
							| 130 | 110 112 117 120 129 | syl22anc | ⊢ ( ( ( ( ( 𝑡  ∈  ( 𝑃  ∩  𝐿 )  ∧  𝑥  ∈  𝒫  𝑡 )  ∧  𝑥  ≼  ω )  ∧  𝑥  ≠  ∅ )  ∧  𝑓 : ℕ –onto→ 𝑥 )  →  ∪  ran  ( 𝑛  ∈  ℕ  ↦  ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) ) )  ∈  𝑡 ) | 
						
							| 131 | 56 130 | eqeltrid | ⊢ ( ( ( ( ( 𝑡  ∈  ( 𝑃  ∩  𝐿 )  ∧  𝑥  ∈  𝒫  𝑡 )  ∧  𝑥  ≼  ω )  ∧  𝑥  ≠  ∅ )  ∧  𝑓 : ℕ –onto→ 𝑥 )  →  ∪  𝑛  ∈  ℕ ( ( 𝑓 ‘ 𝑛 )  ∖  ∪  𝑖  ∈  ( 1 ..^ 𝑛 ) ( 𝑓 ‘ 𝑖 ) )  ∈  𝑡 ) | 
						
							| 132 | 52 131 | eqeltrrd | ⊢ ( ( ( ( ( 𝑡  ∈  ( 𝑃  ∩  𝐿 )  ∧  𝑥  ∈  𝒫  𝑡 )  ∧  𝑥  ≼  ω )  ∧  𝑥  ≠  ∅ )  ∧  𝑓 : ℕ –onto→ 𝑥 )  →  ∪  𝑥  ∈  𝑡 ) | 
						
							| 133 | 42 132 | exlimddv | ⊢ ( ( ( ( 𝑡  ∈  ( 𝑃  ∩  𝐿 )  ∧  𝑥  ∈  𝒫  𝑡 )  ∧  𝑥  ≼  ω )  ∧  𝑥  ≠  ∅ )  →  ∪  𝑥  ∈  𝑡 ) | 
						
							| 134 | 31 133 | pm2.61dane | ⊢ ( ( ( 𝑡  ∈  ( 𝑃  ∩  𝐿 )  ∧  𝑥  ∈  𝒫  𝑡 )  ∧  𝑥  ≼  ω )  →  ∪  𝑥  ∈  𝑡 ) | 
						
							| 135 | 134 | ex | ⊢ ( ( 𝑡  ∈  ( 𝑃  ∩  𝐿 )  ∧  𝑥  ∈  𝒫  𝑡 )  →  ( 𝑥  ≼  ω  →  ∪  𝑥  ∈  𝑡 ) ) | 
						
							| 136 | 135 | ralrimiva | ⊢ ( 𝑡  ∈  ( 𝑃  ∩  𝐿 )  →  ∀ 𝑥  ∈  𝒫  𝑡 ( 𝑥  ≼  ω  →  ∪  𝑥  ∈  𝑡 ) ) | 
						
							| 137 | 25 17 136 | 3jca | ⊢ ( 𝑡  ∈  ( 𝑃  ∩  𝐿 )  →  ( 𝑂  ∈  𝑡  ∧  ∀ 𝑥  ∈  𝑡 ( 𝑂  ∖  𝑥 )  ∈  𝑡  ∧  ∀ 𝑥  ∈  𝒫  𝑡 ( 𝑥  ≼  ω  →  ∪  𝑥  ∈  𝑡 ) ) ) | 
						
							| 138 | 11 137 | jca | ⊢ ( 𝑡  ∈  ( 𝑃  ∩  𝐿 )  →  ( 𝑡  ⊆  𝒫  𝑂  ∧  ( 𝑂  ∈  𝑡  ∧  ∀ 𝑥  ∈  𝑡 ( 𝑂  ∖  𝑥 )  ∈  𝑡  ∧  ∀ 𝑥  ∈  𝒫  𝑡 ( 𝑥  ≼  ω  →  ∪  𝑥  ∈  𝑡 ) ) ) ) | 
						
							| 139 |  | vex | ⊢ 𝑡  ∈  V | 
						
							| 140 |  | issiga | ⊢ ( 𝑡  ∈  V  →  ( 𝑡  ∈  ( sigAlgebra ‘ 𝑂 )  ↔  ( 𝑡  ⊆  𝒫  𝑂  ∧  ( 𝑂  ∈  𝑡  ∧  ∀ 𝑥  ∈  𝑡 ( 𝑂  ∖  𝑥 )  ∈  𝑡  ∧  ∀ 𝑥  ∈  𝒫  𝑡 ( 𝑥  ≼  ω  →  ∪  𝑥  ∈  𝑡 ) ) ) ) ) | 
						
							| 141 | 139 140 | ax-mp | ⊢ ( 𝑡  ∈  ( sigAlgebra ‘ 𝑂 )  ↔  ( 𝑡  ⊆  𝒫  𝑂  ∧  ( 𝑂  ∈  𝑡  ∧  ∀ 𝑥  ∈  𝑡 ( 𝑂  ∖  𝑥 )  ∈  𝑡  ∧  ∀ 𝑥  ∈  𝒫  𝑡 ( 𝑥  ≼  ω  →  ∪  𝑥  ∈  𝑡 ) ) ) ) | 
						
							| 142 | 138 141 | sylibr | ⊢ ( 𝑡  ∈  ( 𝑃  ∩  𝐿 )  →  𝑡  ∈  ( sigAlgebra ‘ 𝑂 ) ) | 
						
							| 143 | 142 | ssriv | ⊢ ( 𝑃  ∩  𝐿 )  ⊆  ( sigAlgebra ‘ 𝑂 ) | 
						
							| 144 | 5 143 | eqssi | ⊢ ( sigAlgebra ‘ 𝑂 )  =  ( 𝑃  ∩  𝐿 ) |